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arXiv · 1708.04756

Topological qubits from valence bond solids

Dong-Sheng Wang·Ian Affleck·Robert Raussendorf
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Abstract

Topological qubits based on $SU(N)$-symmetric valence-bond solid models are constructed. A logical topological qubit is the ground subspace with two-fold degeneracy, which is due to the spontaneous breaking of a global parity symmetry. A logical $Z$-rotation by angle $\frac{2\pi}{N}$, for any integer $N > 2$, is provided by a global twist operation, which is of topological nature and protected by the energy gap. A general concatenation scheme with standard quantum error-correction codes is also proposed, which can lead to better codes. Generic error-correction properties of symmetry-protected topological order are also demonstrated.

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Dong-Sheng Wang, Ian Affleck, Robert Raussendorf. 2017-08-16. Topological qubits from valence bond solids. https://doi.org/10.1103/physrevlett.120.200503

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